I also have simple partial seizures. I avoid nutrasweet/aspartame as well as MSG (monosodium glutamate) and all of its hidden forms. If you do an internet search for MSG and its hidden forms you will find lists of ways food companies hide it in food, or certain ingredients that are excitotoxic to the brain. Some common ones are soy protein isolate, hydrolyzed protein, protein concentrate, yeast extract or extractives. I find that reading labels to avoid these ingredients has really helped with seizure control. It also leads to a more healthful diet because most processed and canned foods have these ingredients. So I have ended up eating a more whole foods diet and feel better.